In this study, the mechanical properties and flexural behaviour of the fibrous cementitious composites containing hybrid, kenaf and barchip fibres cured in cyclic exposure were investigated. Waste or by-product materials such as pulverized fuel ash (PFA) and ground granulated blast-furnace slag (GGBS) were used as a binder or supplementary cementitious to replace cement. Barchip and kenaf fibre were added to enhance the mechanical properties and flexural behaviour of the composites. A seven mix design of the composites containing hybrid, kenaf and barchip fibre mortar were fabricated with PFA-GGBS at 50% with hybridization of barchip and kenaf fibre between 0.5% and 2.0% by total volume weight. The composites were fabricated using 50 × 50 × 50 mm, 40 × 40 × 160 mm and 350 × 125 × 30 mm steel mould. The flexural behaviour and mechanical performance of the PFA-GGBS mortar specimens were assessed in terms of load-deflection response, load compressive response, and crack development, compressive and flexural strength after cyclic exposure for 28 days. The results showed that specimen HBK 1 (0.5% kenaf fibre and 2.0% barchip fibre) and HBK 2 (1.0% kenaf fibre and 1.5% barchip fibre) possessed good mechanical performance and flexural behaviour. As conclusion, the effect of fibres was proven to enhance the characteristics of concrete or mortar by reducing shrinkage, micro crack and additional C-S-H gel precipitated from the pozzolanic reaction acted to fill pores of the cement paste matrix and cement paste aggregate interface zone between mortar matrix and fibre bonding.  

In this study, it is aimed to decrease the weight of the material by using polymer foam materials with lower density instead of commercial polymers which have wide usage area. For this purpose, polymer foam was produced by using an acrylonitrile butadiene styrene (ABS) matrix and an endothermic chemical foam agent using injection molding method. The foam cell morphology, shell layer thickness and mechanical properties of the final part were investigated taking into consideration the weight-changing ratios of the foam agent content (1-1,5-2-2,5-3%).

Structures are damaged every year in earthquakes. The survivability of structures in an earthquake is important as lives are lost, cities can be brought to their knees and billions of dollars are required to repair damaged structures. For these reasons, researchers across the globe are trying to create structures with increased performance and reduced damage after experiencing an earthquake. This paper is a state-of-the-art review of using shape memory alloy (SMA) as reinforcement for structures in seismic areas. SMA is an emerging, innovative material, which possesses unique characteristics, unlike conventional materials, which allows it to change its shape through heating or unloading. These phenomena, known as shape memory effect and pseudoelasticity, make SMA suitable for reinforcing structures in seismic areas due its low elastic modulus, ability to dissipate energy and capacity for large strains. Traditional methods for new constructions and strengthening are discussed and compared with innovative methods utilizing SMA and two case studies of SMA being used in seismic retrofit systems to repair historical structures damaged in earthquakes are provided